To add or subtract expressions, expand them to make their denominators the same. Least common multiple of $a-3$ and $3-a$ is $a-3$. Multiply $\frac{9-6a}{3-a}$ times $\frac{-1}{-1}$.
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of $a-3$ and $3-a$ is $a-3$. Multiply $\frac{9-6a}{3-a}$ times $\frac{-1}{-1}$.
